Pitman counterbalance



Patented Mar. 8, 1932 UNITED STATES CHARLES C. SHIPIVLAN, OF BREA, CALIFORNIA IPITMAN COUNTERBALANCE Application filed September 30, 1930. Serial No. 485,420.

The object of my invention is to provide a new and improved means for counterbalancing the weight of a string of the rods used in pumping deep wells.

t is well known that the weight of the pump rods must be counterbalanced to prevent excessive power consumption and undue strains on the pumping equipment. It is customary to provide counterbalances, which in heretofore have been attached either to the band wheel by which the pumping crank is actuated or to the crank itself or to the crank end of the walking beam.

I have discovered that it is highly advantageous to attach the counterbalance weight to the pitman or preferably to a downward extension thereof, the advantages being that the weight is placed much lower and in a position where it is readily accessible; that the weight is taken off revolving parts and reciprocating strains are thereby avoided, and finally the wear on the wrist pin bearing is greatly reduced and it is made much easier to lubricate.

In the accompanying drawings Fig. 1 is a side elevation of the customary Samson post and walking beam of an oil pumping rig connected operatively with a steel or wood pitman bearing my improved counterbalance.

Fig. 2 is a side elevation, in section, of my counterbalance and the lower end of the pitman to which it is attached.

In the drawings, 10 is the Samson post, 11 the walking beam, 12 the pitman and 18 the crank these being parts of the usual pumping mg.

I extend the pitman downwardly below the wrist pin bearing as indicated at 14 and fix in this extension a pin 15. From this pin I suspend a suitable weight 16 which may be in the form of a heavy plate, flat on the side which comes next to the pitman. To this plate may be attached any desired number of additional weights, in the form of rectangular plates 17, by means of the bolts 18.

I prefer to suspend this weight from a pin, as shown in the drawings, in such manner that it will maintain an upright position, but it is within the scope of my invention to attach the weight rigidly to the lower extremity m of the pitman.

I claim as my invention:

1. In a well pumping rig having a pitman:

a counterweight for the pumping rods having the form of a plate and being swingingly at- 5:, tached to the extreme lower end of said pitman at a point near the upper edge of said plate and substantially on the vertical axis of said plate.

2. An apparatus according to claim 1 in which the plate bears transverse openings for the reception of bolts, whereby additional plates may be attached to the first.

3. An apparatus according to claim 1 in which the plate is suspended in a position on the central axis of the pitman from a wrist pin passing through the latter, said weight being able to swing freely on said wrist pin.

In witness that I claim the foregoing I have hereunto subscribed my name this 25th day of Sept, 1930'.

CHARLES C. SHIPMAN.

M s,19s2. WESHORE 1,848,6 0

ROTARY COMPRESSOR Filed April 9, 1928 2 Sheets-Sheet l z Z5 Z3 z O O l g I I March 8, 1932. w E SHORE 1,848,670

ROTARY COMPRESSOR Filed April 9, 1928 2 Sheets-Sheet 2 Patented Mar. s, 1932 UNITED, STATES PATENT OFFICE W'IIIIIIAI E. SHORE, OF WEST NEW BRIGHTON, NEW YORK, ASSIGNOB TO SHORE 003- PORLTIOH, OI DOVER, DELAWARE, L CORPORATION OF DELAWABE OODBESSOB application fled April 0, 1m. Serial m gesaaa.

The principal objects of this invention are, to improve the construction of a compressor such as described in my pending apphcatlon No. 160,194 filed January 10th 1927 2 whereby I the strain and wear on the working parts will be reduced to the minimum, and whereby the efiiciency of the machine will be considerably enhanced.

The principal features of the invention con- I It sist in the novel construction of the rotary vane member and the means for supporting same whereby an impeller vane operat ng m a radial slot in the rotor member is supported by an extension thereof having bearing sur- 15 faces engaging bearing supports arranged at either side to maintain the axis of the vane in parallel relation with the rotor axis and to preventaxial movement of the impeller.

A further feature of importance in the present invention consists in the novel construction of the compressor casing, whereby the discharge from onecylinder is staged within the pump casing to supply the a jacent cylinder, thereby subjecting the medium under compression to substantially instantaneous changes of pressure and temperature with the minimum oftransfer of heat to the compressor mechanism.

A still further feature of importance consists in the novel arrangement ofa bye-pass between the initial intake passage and the finaldischarge passage to enable the recycling of the medium'under treatment, to effect a raising of the operating temperature.

In theedrawings, Figure 1 is a vertical midsectional and part elevational view of a compound compressor unit constructed in accordance with the present invention.

Figure 2 is a horizontal sectional view of the unit illustrated in Figure 1.

Figure 3 is. an end elevational view looking in the direction of arrow, Figure 1.

Figure 4 is a sectional elevational view taken through a first stage cylinder on the line 44 Figure 2.

Figure 5 is a sectlonal elevational view.

through the secondstage cylinder taken on the line 55 of Figure 2.

59 Figurefi is a perspective 'ew of the double im Her vane showing the bearing supports or the vane in sectional perspective.

Figure 7 is a central sectional view through the dual impeller vane.

In my fprevious application 'I have shown a pair 0 pump cylinders eccentrically arranged and each having therein an eccentric rotor and an impeller vane operating in said cylinders and engaging said rotors and formed of a rigid unit comprising two right angularly placed vanes but it has been found in practice that much higher speeds of operation can be obtained b reason of the improved construction of t e impeller vane and its bearing supports.

It has also been ascertained that the two cylinder casings may be advantageously c'onstructed from the one pattern, thus facilitating the handling of the mechanical construction of the device.

In the present construction each c linder casing 1 is formed with a cylinder 0 amber 2 which is of a peculiar formation to accommodate the peculiar movement of the impeller vane.

The transverse axis AA extending through the division wall 3 is arranged in c alignment with the axis of the rotor 4, and the impeller 5 when in engagement with the division wall extends across the diameter of the cylinder and engages the opposite side thereof. 4

The axis of the rotor is offset laterally from the centre of the cylinder towards the division wall '3 and the walls of the cylinder 85 casing on either side of the transverse axis curve outwardly from the cylindrical to accommodate the movement of the impeller vane which by the rotation 'of the rotor moves ofi the axis of the cylinder.

Each of the casings 1 are formed with the cylindrical recess extensions 6 eccentric to the cylinder chamber 2 into. which the outer end of each of the rotors 4 extend.

A sleeve extension 7 projects from the cy- 95 lindrical recessed portion 6 and is concentrictherewith and in each of said sleeve extensions are arranged the roller and ball bearing races 8 and 9 respectively.

- The rotors are provided with the shaft ex- 10 a centrally arranged shank portion 2Owh1ch' The disc 21 is spaced from the inner edge of each vane section a distance equal to the 13 and a ring 14 formed with a flange 15 on' its perimeter is fitted into said recesses and thus centralizes the two casings.

- Aflat ring 16 abutsthe outer edge of the flange of the-ring 14 and fits in thcopposite counter-bore. 'These two rings are constructed of a hard bearing material and are aces arallel.

Eac of the rotors4 is formed with a transverse slot'17 and these are set in right angular relation to'each other to receive the right angularly disposed sections of the impeller vane. v

i The impeller vane is formed with the two flat sections 18 and 19 arrangedv in right another centrally of their length. a

Each of the vanes'ections is formed with flares outwardly fromtheir flat faces to meet the right angularly disposed circular flange or-disc21.-

thickness'of ,therings 14 .and 16 and the thickness of the disc 21 is equal to the depth of the flange 15 of the ring 14.

The flat surfaces ofthe disc 21 are very v I accurately ground to forms. sliding bearing against the inward faces of the rings 14 and 15 and as the rings-14 and 15 are rigidly supported between the abutting end faces of the icylindrical casings 1, 'bearing supports are provided which form a very rigid bearing for the impeller vane.

" The rings 14' and 16 have to be divided into half sections in order that they may be placed around the disc 21 of the impeller vane and it is preferable to score'these discs on their outward sides andthen crack them to break them into half sections so that they will when fitted together form a fluid tight joint without unnecessary machine. work.

s This construction of'the impeller vane, to-

gether with the arrangement of the bearing surfaces therefor in the form-ofrings described, is extremely important. .The rings are centered in the cylindrical casings and virtually form apart thereof and constitute" the-inward end walls of the cylinder chambers, as the ends of the rotors abut the outward faces of said rings in sliding contact.

.The end faces of the rotors abutting the 'ri'ligsl i and 16 and the enga ing faces of the disc 21 and the rings 14 an 16 are preferably li uid sealed-with a suitable lubricantwhich wi be'maintained in contact with the. ii-engag ng surfaces by centrifugal action.

ground very accurately with their inward.

* to the intake of the first cylinder an other means of lubricating the contacting surfaces may of course be ado ted or materials may be used which will ispense with lubrication.

Each of the cylinder casings is provided with intake and outlet recesses 22 and 23 respectively arranged on opposite'sides of' the division wall 3 and these recesses open sage 25 to the inlet chamber of, the adjacent cylinder casing as the compression chambers of the two cylinder casings are in diametrical- .ly ofiset relation as is seen' particularly on reference to Figures 3, 4 and 5. I

The intakeof one cylinder chamber is" ranged at the bottom, while 'the'intfake "of; the other cylinder chamber is arranged at .the' top, consequently the discharge of: the gular'relation to each other and crossmg each second cylinder is arranged "in juxt'a ositioiij apes: sage'26 connects the chambers A valve seat 27 is arranged in 6 .16. of the. casings in the passage 26 and thetvalve 28 is arranged in the other cylinder casing adapted to close against the valve seat. .to this I compressed fluid discharged from the sepond close the interconnecting passage but when such valve is open it will, be seen that the stage casing may becirculated backint'o'. the. primary intake of the first cylinder 'casing.

It will be understood from this description. that the arrangement of the pair of ground guiding rings engaging the rigid sectionv of the rotor vane will hold thevane perfectly true in. relation to its axis, preventing move intheir natural orbit between the two centres of the adjacent rotors. This orbit. is created by the sliding .of the vanes in the slots atv right angles to each other with the rotors rotating in unison on difierent'a'xes.

The arrangement of the central d1sc main-.

tainsthe vanes in perfect alignmentwith the slots at all times and prevents theyanes from tilting int-he rotor slots through the necesthe vanes of the impeller ina constantly. triieposition in relation to the respective'rotorsi" n? 'play or weaving, while allowing the vanes to movement of the vanes Another im ortant feature of'this central-' ized disc bearing is that it prevents endwisemovement and consequently end thrust of:-

the ends of the vanes against the ends of. the

I pressure. The word compressor as used is to be so understood.

a the inner ends of t e of the vanes against the rings, the thrust all being taken on atrue flat disc surface.

i It also be seen that the centrifugal action maintains a thorough lubrication between the thrust bearing surfaces formed by intercalated compensating bearing. I

Though in the specification and claims I V have termed my device a compressor, it will be understood that its use does not necessanly involve the building up of any par- "*ticular degree of pressure. 7 The pressure at the outlet end of the device obviously depends upon the conditions and ma be greater than or equal to, or-less than atmospheric hereim What I claim as my invention is 1. ha rotary compressor, the combinatlon with a pair of cylinder casings eccentriv. cally arranged in.-relation one to the other and rotors eccentrically mounted in each of v said casings and eachhaving a transverse slot therein and an impellerformed of a pair of right angularly arranged vanes engaging the transverse slots ofsaid rotors, of means operating in a fixed plane interposed between said nght an arly arranged vanes in rightan ar relation to the rotor axes, and adapt- --ed y contact with fixed portions of the compressor to support saidvanes in true parallel relation to the. axes of said rotors.

. 2. In a rotary compressor, the combination with a pair of cylinder casings eccentrically arranged in relation one to the other and rotors eccentrically mounted in each of said casings, and each-having a transverse slot therein and an impeller formed of a pair of right angularly arranged vanes engaging .the transverse slots of said rotors, of an annular member. inserted between the cylinder .casin and abutting the adjacent ends of the rotors and closing the chambers between the rotors and the cylinder walls, and a rigid annular extension on said impeller engagmg said annular member in sliding rotative contact.

3. In a rotary compressor, the combination with a pair of cyhnder casings eccentrically arranged in relation one to the other and rotors eccentrically mounted in each of saidcasings and each having a transverse slot therein and an impeller formed of a pair of right angularly arranged vanes engaging the transverse slots of said rotors, of a flat disc rigidly united with and forming a unitary part of the impeller having its flat faces spaced from the inner edges of the vanes thereof, and a pair of spaced ring members rigidly secured between the abutting ends of the cylinder casin and extending between impeller vanes and the flat faces of said and forming a guide for the impeller.

4. A rotary compressor, .com n'smg' a air of cylinder casings eccentricall y arranged in relation one to the other and havin concentrically arranged counterbores in t eir open abutting eiids, a flanged bearing ring seated in one of said counterbores and extending into the other counterbore. to position the cylinders, a bearing arranged in the opposing counterbore an having its adjacent ace spaced from'the face of the aforesaid bearing ring, a disc rotativelyvand slidably arranged between the spaced faces of said bearing rings having raised projections from either'side each terminatin in an impeller Lvane extending into the a jacent cylinders and arranged in right angular relation to each other, and transversely slotted rotors journalled eccentrically in offset relation in said cylinders. I '5. A rotary compressor, comprising a pair of cylinder casin s each having a cylinder chamber arrange in diametrical offset relation the one to the other, rotors arranged one in each cylinder chamber and in diametric ofiset relation the one to the other each engaging an opposite side of'the cylinder wall, inlet and dischargepassages in each of said cy inder casings communicating with the cyhnder chamber, the discharge from one cylinder chamber being connected with the inlet to the adjacent cylinder chamber, an impeller formed of a pair of rigidly united right angularly arranged vanes extending transversely through the axes of said rotors, and means interposed between the opposing ends of said cylinder casings and the opposing end faces of said rotors forming a seal therebegaging an opposite side of the cylinder wall,

inlet and discharge passages in each of said cylinder casin communicating with the cylinder cham r, the discharge from one cylinder chamber having a passage connected with the inlet to the adjacent cylinder chamber, and the inlet of the first cylinder chamber being connected with the discharge from the second cylinder chamber, a valve controlling the passage between the discharge of the second chamber and the inlet of the first chamber, a disc rotatably mounted between said cylinder chambers and having rigid impeller vanes extendin said rotors, and means for supporting said discin a lane in right angular relation to the axes o the cylinders.

therefrom in right angular relation to eac other and engaging 

